THERE WERE GREAT cheers from all the right corners of Maryland, Virginia, Pennsylvania and anyhere else with a respect for Chesapeake Bay when Gov. Harry Hughes first called for serious action to save this unique waterway from the ravages of overdevelopment and other sources of pollution. Today, the governor's interest in the issue is still strong in Annapolis and the state legislature is taking an important step to protect the bay area. But Eastern Shore legislators aren't happy about it -- and their determination to weaken the effects of the latest legislative measures hasn't flagged at all. So far at least, supporters of House and Senate resolutions to limit development around the bay are resisting efforts to undo their good work, and they should hold fast.

The protection moves approved in each house focus on the bay shoreline areas; building would be limited to one house every 20 acres, which follows guidelines drawn up by a governor's task force as reasonable ways to allow limited growth. The Eastern Shore lawmakers have been pushing measures to allow construction of one dwelling on every eight acres. They argue that the tougher restrictions would hurt the Eastern Shore economy. Even if that proves to be the case, the answer shouldn't be to wreck the bay, but to help the region with other forms of assistance.

During debate in the House the other day, one Anne Arundel County lawmaker who sympathized with the plight of his Eastern Shore colleagues said, "Most of us realize that what the Eastern Shore is saying is legitimate. You're taking away from the Eastern Shore the most valuable asset they have, and that's their waterfront." But the Chesapeake Bay is a far greater asset -- belonging not to a county or a shore region or even a single state. For it to survive, the shoreline must be protected against development excesses. The latest regulations should be allowed to take effect and be mease reasonably determine whether changes might be made without wrecking the whole point of this effort.